Steam-heating system



Aug. 21, 1928.

J. A. DONNELLY STEAM HEATING SYSTEM Filed June 18, 1924 54F l 1 \N\ MEWF INVENTOR. 7Z7/r7 5 D nne/W, BY

A? M ,1 3 WA TTORNEYS.

w ilk W WZPAVQ 3 AN aw 9? Patented Aug. 21, 1928.

UNITED STATES PATENT OFFICE.

JAMES A. DON'NELLY OF BROOKLYN, NEW YORK, ASSIGNOR T0 WABREE' WEBSTER &

COMPANY; A CORPORATION OF NEW JERSEY, I

STEAM-HEATING SYSTEM.

Application filed June 18, 1924. Serial 110,720,829.

This invention relates to regulating means for insuring the properamount of steam to be supplied to heating systems and to the respectiveradiators thereof.

In commercial practice with installations involving distribution ofsteam to a large number of radiators, as in the case of hotels,apartment houses and oflice buildings, great difiiculties have beenexperienced in insuring proper distribution of the steam throughout allthe radiators and in obtaining uniform temperature conditions, and thesedifiiculties have been increased owing to various conditions due to thecharacter of the exposures (such as-northern and southern exposures) andcauses due to shape of building Which induces abnormal air currents.With the radiators 4 inducing the necessary steam circulation therein,but such systems 1 have been costly to install and diflicult to keep insatisfactory operative condition. They also require constant attention,and, moreover, are incapable of varying the radiator heating capacity onthe modulation prlnciple, and therefore required additional automaticthermostatically controlled means for alternately admitting and shuttingoff the supply of steam to each radiator to control the time periods inwhich it is acting as a heater to maintain the normal room temperaturerequired. All of these difficulties are entirely overcome with myimproved system in that a vacuum and vacuum creating means may beentirely dispensed With and the steam, which is delivered into thesystem, so subdivided as to supply the needs of the different portionsof the distributing mains, pipes, rises ta, whereby it is delivered intothe, radiators only in the'exact quantity required, the circulation thusproduced insuring the exact predetermined results as to room temperatureand, at the'same time, permit said room temperature to be varied to thedesired extent at will, I 'whilenot exceeding the predetermined maximumtemperature required. By the employ ment of my improvements, steam issothoroughly subdivided and accurately distributed among all of theheaders, risers and branch pipes, that each radiator may be definitelysupplied with the required steam, whereby uniform temperature isautomatically assured throughout the building, thus enabling a largesystem to be operated perfectly as a pressure system with theelimination of vacuum requirements and the attendant complicatlon ofvacuum pumps and other apparatus pecuhar to vacuum systems.

One objectof the invention is to provide suitable means for distributingto radiators arranged in groups the proper proportion of steamnecessary. therefor as an entirety, and also as required by therespective radiators of such groups, whereby the different-groups ofradiators may operate to maintain a uniform temperature under differentoutside temperature conditions to which they may be respecjavelysubjected during the same period of ime.

Another object of the invention is to provlde an improved apparatus forinsuring the proper amount of steam to be fed to the radiators bycontrolling the steam supply and proportionally distributing the steamto respective groups of radiators and to the individual radiators ofsaid groups in exactly the proper relative quantities to insure uniformheating of the building thereby.

Other objects of the invention are to improve generally the simplicityand efliciency of steam systems and to provide apparatuses of this kindwhich are economical to manufacture and operate and which are very easyto control. v

Still other objects of the invention will appear as the descriptionproceeds; and while herein details of the inventionare described, theinvention is notlimited to these since many and various changes may bemade without departing'from the scope of the invention as claimed.

. The inventive features for the accomplishment of these and otherobjects are shown herein in connection with a heating system having, inaddition to the usual large horizontal steam main into which the initialsupply of steam is delivered, a plurality of branching mains or risersopening from the horizontal main at different distances from the sourceofsteam supply, and a plurality of radiators forming separate groupsseverally receiving steam from the respective risers or branch mains andarranged at different distances from the connection of the risers orbranch mains with the steam main, when characterized by having means fornormally supplying the horizontal steam main with steam at a pressureabove atmos' pheric pressure and in quantity less than sufii cient, inmedium cold weather (such as 50 F, for example), to fill all theradiators, to gether with means having orifices of predetermined sizesrespectively arranged in each of the risers or branching mains adjacentto their inlet ends and proportioned to regulate and supply steam fromthe horizontal main into the respective risers or branching mains inuantity (during saidmedium cold weat ier) insufficient to fill thegrouped radiators in communication with the respective risers or branchmains, and separate means arranged between the individual radiators ofeach group and their respective risers or branching mains, each havingan Orifice of predetermined size for regulating and nor" mallyadmitting, to the radiators of the respective groups, steam at or aboveatmosphcric pressure and in quantity insuflicient (during said mediumcold weather) to completely fill the radiators, the orifices pertainingto the radiators of the several groups or several radiators of anygroup, differing in area to compensate for the different distances ofthe respective radiators of the groups from the horizontal main, byreason of which definite and proper distribution of steam is normallyinsured to the numerous radiators and.

uniform heating of large buildings made possible with a minimumconsumption of steam which. in actual practice, has reach-ed a saving ashigh as fifty-seven per cent of the steam previously required in themost approved pressure and vacuum systems in general use.

My invention also comprehends other features of improvement which arefully set out hereinafter and defined in the claims.

In the accompanying drawing, showing by way of example, one of manypossible embodiments of the invention,

Fig. 1 is a diagrammatic. side elevation of the system, the means forinitially supplying the steam being shown partly in section;

Fig. 2 is a fragmental longitudinal sectional view. partly in elevation,of a conduit with the orificed disk therein;

Fig. 3 is a longitudinal sectional view of a union with the orificeddisk therein for regulating the steam supplied to the risers and branchpiping; and

Fig. 4 is a fragmental.diagrammatic sectional view of another form ofsteam. sup-plying means.

The steam is supplied from a boiler or any other suitable source to oneor more horirisers 12 are fed by the supply main and in turn feedradiators 14. A control means 15 is interposed in said main forcontrolling and admitting to the main 11 the total quantity of steamrequired by the system. As shown this control means includes the valve16, and flow orifice 17 with a pressure chamber 18 thcrebetwcen withwhich communicates the pressure gauge 19 controlled by the pressure inthe pressure chamber for controlling the flow of steam.

The lower part of each respective riser is provided with an offsetportion in which is interposed a union 26 (Fig. 3) provided with a disk27 having therein an orifice 28 of a size calculated to compensate forthe pressure drop due to friction alone of the horizontal distributionin the supply main 11 corresponding to the distance of the riser inletfrom the control means 15 for admitting to each riser the properproportion of steam required for the radiators fed thereby. While anysuitable union 26 may be used, the one shown in Fig. 3 will answer thepurpose. It

includes a threaded terminal 30 received on one section of the offset 25and provided with an e'xteriorly threaded thickened inner end 31 havinga transverse inner end face 32 leaving a large central opening 33. Theterminal 30 may be provided with wrench received faces 34. A secondterminal received on the other section of the offset is provided at itsintermediate part with wrench receiving faces 41 and provided at theinner end with an outer shouldered flange 42 and a transverse end face43. The disk 27 is secured between said terminal parts 30 and 41 andagainst said transverse faces 32 and 43. The central flow orifice 28maybe formed with a lip 44 turned in the direction of flow of the steam. Aninteriorly threaded hexagonal ring 45 received on the threaded flange 31and provided with an interior flange 46 engaging said shouldered flange42, holds all of the parts firmly together, and is removable to permitinterchange of the disks. A suitable disk 50- (Fig. 2) is alsointerposed between the respective radiators 14 and the associated risers12 and is provided with an" orifice 51 for admitting to each radiatortheproper proportion of steam for the respective radiators, each orificebeing of a size calculated to compensate for the pressure change due (1)to the friction of the vertical distribution of steam in the riserscorresponding to the distance of the radiator from the main 11, (2) tothe decrease in atmospheric pressure due to altitude, and (3) to thedecrease 'in pressure due to the weight of the steam.

WVhile the disks 50 may be interposed in many different ways, herein Ishow each radiator inlet valve 55 provided with an exteriorly threadedconduit 56 (Fig. 2) projecting from the side of the valve casing andprovided with zontal supply mains 11. Branch pipes or a transversepartial partition 57 provided with an opening and an outer inwardlyinclined face 58 receiving a coned edge face 59 of a terminal 60exteriorly threaded at its outer end 61 for receiving a union andprovided at its-intermediate part with wrench receving faces 62 and atthe inner end with a shouldered flange 63, said inner end also providedwith an inner shoulder 65 against which said disk is secured in theterminal 60. An interiorly threaded hexagonal ring 66 received on thethreads of said conduit 56 and provided with an inward annular flange 67engaging said shouldered flange, holds the parts firmly together, and isremovable to permit interchange of the disks. Drip pipes 7 O drain therisers 12 into the return main 71 to which also return the branch returnpipes 72 draining the radiators 14 through outlet pipes 74 and providedwith air valves 75.

' From the foregoing it is evident that the attendant may, by the valve16, control the proper total initial quantity of steam required for thesystem in accordance with outside weather conditions, and that theorifices 28 will control and admit to each group. of

radiators the proper proportion of steam required for the radiatorsthereof, while the orifices 51 will control and admit to each individualradiator the proper proportion of steam therefor. When the weather isvery cold. the attendant will admit enough steam by valve 16 to heat thelarger part or whole of. each radiator but when the weather is warmer,he will admit onlyanough steam to heat part of each radiator, the extentof the heat radiating surface being controlled in accordance with theamount of steam supplied to the whole system,a1id in accordance with theoutside weather conditions, as above explained.

It is not only the object of this invention to provide a means forcontrolling the total amount of steam supplied to a heating system,.butalso to distribute the steam equally among all individual radiators.

' Since the total amount of radiating surface provided for-heating abuilding is calculated for the lowest outside temperature condition, itfollows that, for economical operation, the heating eflect of theradiators must be reduced for all milder weather conditions. This maybedone to a slight degree by reducin g the pressure and temperature of thesteam or by reducing the quantity by hand manipulation of each radiatorinlet valve. But I prefer to do it on a larger and more effective scaleby controlling the quantity of steam ad,- mitted at the main supply,keeping the delivery pressure substantially constant, and then provide,firstly, means to regulate the proportionate flow of steam to eachgroup. or section of the piping system, and secondly, to each radiator.

In my investigation as to the details of this problem, I discovered thatin buildings of any considerable height it was necessary to take intoaccount the variations in atmospheric pressure due to altitude. This ledme to adopt a system of dividing the apparatus into groups, providing anorifice in each of the steam riser connections, so that with the totalquantity of steam under proper and accurate control, a propersub-division of this quantity can be effected to each riser. Thisallowed for an adjustment to compensate for the friction of the pipingin the horizontal distribution of the steam. Orifices provided for eachradiator were then calculated for the combined effect of the riserfriction and the change in both atmospheric and steam pressure due toaltitude. This calculation may readily be made by anyone familiar withthe weights of the two fluids and the laws governing the flow of steam.

. However, as the difference between the weight of the column of steamand air is constant, while the difference in friction is as the squareof the velocity, no correction can be made forthe combination ofthe twowhich .and lower atmospheric pressure at the top oft-he riser. In thelatter, thehighest steam pressure and lowest air pressure are at the topof the riser, and the lowest steam pressure and highest air pressure areat the bottom of the riser. I

Where the source of steam supply is at low pressure, the quantity ofsteam may be controlled by keeping the pressure constant and varying theopening, or by providing a means of draft control, such as is shown inmy application Serial No. 47 2,229 filed May 24, 1921.

Where the source of steam supply is at high pressure, I prefer to keepthe orifice through which the steam i supplied of constant size and varythe pressure uponit, which may be done with the controlling means abovedescribed and shown in Fig. l. x

Where the steam supply is at low pressure, it may come either from a lowpressure steam boiler or a low pressure street steam plant,

or it may be exhaust steam at low pressure.

manner. One of thefe control valves is placed in each of the branchmains 11 leading to a portion of the building, and each is adjusted inaccordance with outside temperature and wind variations, to the properamount of opening.

Where the steam supply is at high pressure, it may be either from highpressure boilers, or a high pressure street steam plant, or highpresiure steam used to supplement the supply of exhaust steam. Underthese conditions, a chamber is provided, equipped on the inlet with aspecial throttling valve, and on the' outlet with a calibrated flownozzle or orifice. With a gauge to indicate the ressure on the chamber,the amount of steam furnished to the heating system through the flownozzle is under very exact control of the operator for all varyingdemands of the heating system.

lVith either method of supply control, the fixed orifice with varyingpressure, or varying orifice with fixed pressure, the sub-division ofthe steam to the various risers is the same. A controlling orifice plateis placed in the'union flange of each steam riser connection, the areaof which is calibrated for the amount of steam required by the connectedradiation, under the conditions of pre sure as affected by the frictiondrop of the steam main to each riser connection.

With either method of control, the main supply may be divided intoseveral groups, and these may have more or less relation to the buildingexposure as well as to the points if compass.

l have found in my experience with this sy-tem, that building exposuredue to its loca tion, as Well as points of compass, are very importantfactors to be considered in connec tion with the distribution of steam,and es pecially distribution of fractional quantities. The combinationof a controlling orifice in a riser and a distribution orifice for eachradiator makes it possible to change the amount of team supplied to awhole side of a building, hr to a particular section, by the correctionin size of the riser orifice, without the necessity of changing theorifice disk for each radiator, which eliminates a considerable amountof work. In cases where additional radiation has to be added, the riserorifice only has to be changed, and not the individual radiatororifices, which would be the case if the control depended entirely upona distribution orifice for each radiator, without the master controlling orifice in the riser. This is also the case where errors aremade in figuring the friction of the steam main, which may be due to anunusual combination of fittings or other causes.

No claim is made in this application for the method of supplying steamfrom the source to the radiators herein described.

I claim as my invention:

1. A steam'heating system, wherein there are associated and combined, asource of steam supply, a substantially horizontal steam main, aplurality of branching mains or risers respectively opening from thesteam main at different distances from the source of steam supply, aplurality of groups of radiators of which a separate group is connectedto each of the branching main or risers and receives steam therefrom,fixed orifices between the several radiators of each group and therespective branching mains or risers to cause the steam therefrom to beSupplied. to the radiators in predetermined quantities, means incommunication with the source of steam supply for initially supplyingthe system as a whole with steam of a predetermined quantity requiredfor all of the radiators thereof, means having orifices of predeterminedarea arranged in the respective branching mains between their connectionwith the radiators and the substantially horizontal steam main and eachsuch orifice proportioned as to area to insure the passage of thepredetermined quantity of the steam required by the radiators of thecorresponding group.

2. The invention of claim 1, wherein further, the areas of the fixedorifices for the radiators increase per unit of heating capacityproportionally as said radiators are positioned more distantly from theorifices of the branching mains or risers which supply them with steam.4

3. The invention of claim 1, wherein further, the areas of the fixedorifices of the branching mains or risers controlling the sup ply ofsteam to the respective radiator groups increase per unit of heatingcapacity proportionally as said radiator groups are positioned moredistantly from the initial source of steam supply.

i. The invention of claim 1, wherein further, the means in communicationwith the source of steam supply for initially supplying the system as awhole with steam of a predetermined quantity comprises an expansionchamber, a flow orifice interposed be-' tween the expansion chamber andthe substantially horizontal steam main of the system, and a controlvalve interposed between the expansion chamber and the source of steamfor admitting steam to the expansion chamber at a greater pressure thanmaintained in the horizontal steam main to provide a predetermineddifferential across the flow orifice.

t Signed at New York, in the county of New York and State of New York,this 17th day of June, A. D. 1924.

JAMES A. DONNELLY.

